Dental spotlight



E. STROM DENTAL SPOTLIGHT Nov. 3, 1959 Filed April 10, 1956 2Sheets-Sheet 1 In ve n/on MM Nov. 3, 1959 E. sTRoM DENTAL SPOTLIGHT 2Sheets-Sheet 2 Filed April 10. 1956 nited States Patent DENTALSPOI-LIGHI Erik Strom, Eslov, Sweden App1ication April Q1956, Serial vNo. 577,411 Claims priority, application Sweden April 15, 1955 v V 1Claim. (Cl. 240-4115 The present invention generally relates to lightingdevices, and more particularly tolighting sets for work and surgicaloperation purposes.

The invention has for its'principal object to provide a lighting set forwork and surgical operation purposes and particularly adapted to be usedby dentists, and which has the advantage over and above priorconstructions for this purpose that it will deliver a well-defined ovalor rectangular field of illumination without any appreciable formationof shadows.

A further object of the invention is the provision of a lighting set ofthe kind referred to whichis conveniently adjustable into any desiredposition.

For the objects stated, a work and surgical operation lighting setaccording to the present invention is mainly characterised in that theset comprises an ellipsoidally cup-shaped reflector shade on the majoraxis of which the source: of light, such as a frosted filament lamp, isdisposed at one focal point while the locality of operation, such as apatients mouth, is intended to be disposed at the other focal point. Thereflector opening is covered by a glass having vertical flutes in spacedparallel interrelation adapted to refract the rays of light in a mannerto cause the light spot at the locality of operation to appear as awell-defined substantially oval or rectangular field of lightintensively illuminating the region of the patients mouth.

Further according to the invention, the reflector shade may be attachedto one end of a parallelogram linkage arm mounted at its opposite end soas -to be angularly adjustable about a vertical axis. Preferablydisplaceably mounted on one link of' said parallelogram linkage arm is aresiliently loaded abutment member which carries, preferably through theintermediary of anti-friction bearing means, a roller adapted to beurged into engagement with a camming track which is fixedly locatedrelative to said parallelogram linkage arm. This enables the lightingset always to be readily adjusted into the most suitable position.

Further characteristics and structural features of the invention will beset forth or become apparent from the following description inconjunction with the accompanying drawings which illustrate anembodiment thereof by way of example, and in which:

Fig. 1 is'a side elevation of the lighting set;

Fig. 2 is a plan view thereof;

Fig. 3 is a cross-section through the reflector on an enlarged scale;

Fig. 4 illustrates the light spot obtained by the use of the deviceaccording to the invention, as compared with a light spot as normallyobtained; and

Fig. 5 is a front view of the reflector covering glass.

Referring now to the drawings more specifically, nu meral 1 designates awall to which the lighting set is mounted so as to be angularlyadjustable about a vertical axis in a housing or mounting 2 which lattercould also be combined with an electric transformer. The in- PatentedNov. 3, 1959 ner end portion of the lighting set consists of a rigid arm,3 the inner end of which is bent down at: right angles and isjournalledin the housing or mounting 2, whereas the arm 3 is provided at itsextreme end with .a vertically extending pivot pin 4 receiving thereon aforked bracket 5 which is angularly adjustable about the pivot pin 4 ina horizontal plane. Attached to the forked bracket 5 are the near endsof two spaced parallel tubular links 6 and 7 which are articulated tothe bracket 5 by means of pivot pins 8. Received within the upper link 6is a coiled compression spring 9 engaging at its rear end an abutmentbracket 10 slidably mounted on the link 6 and being provided with a camfollowing roller 11 which is urged by the spring pressure firmly againstcamming tracks 12 formed on the forked bracket 5.

The extreme ends of the two parallel links 6, 7 engage a front-endforked bracket or holder 13 and are articulated thereto by means ofpivot pins 8. The forked holder 13 is provided with a vertical pintle 14on which an arcuate yoke 15 is mounted so as to be angularly adjustablein a horizontal plane. Mounted in said yoke 15 by means of horizontallyaligned trunnions 16 is an ellipsoidal reflector shade 17 (see Fig. 3).Axially displaceably mounted within a bushing 19 in the bottom center ofthe reflector is a lamp socket 18 having fitted into its front end afrosted filament lamp' 20', an electric connecting cable 25 beingintroduced through the lamp socket 18. The front opening of thereflector shade 17 is covered by a glass 23 being spaced from the edgeof the reflector shade 17 by a ventilation clearance 26. Mounted on arod 22 secured centrally on the internal face of the glass 23 is a smallcup-shaped anti-dazzle shade 21 disposed opposite the filament lamp 20.The

glass 23 is formed in its internal face with flutes 24 (see Fig. '5).The glass 23 may be made of heat-absorbing shatterless Plexiglas which,in conjunction with the ventilation feature of the reflector shade 17,will ensure an extremely low development of heat.

When using the lighting set, the filament lamp 20 should be so adjustedas to be situated at one focal point B of the ellipsoid of which thereflector shade 17 forms part whereas the locality of operation A in theregion of the patients mouth M (Fig. 4) is localized to the other focalpoint B The rays of light L emitted by the filament lamp 211 and beingindicated by broken lines, after they have been reflected by thereflector 17, will be refracted when passing through the fluted glass-23 in a manner to cause the locality of operation A (Fig. 4) to beilluminated intensively by a substantially rectangular and relativelylarge field of light F rather than by a circular light spot P of smallarea as is the case when using lighting sets of the previously existingtypes.

By this means there will be obtained in the region of the patients mouthan essentially improved and intensified illumination of a larger andwell-defined Zone, and without any-harmful formation of shadows. It isto be understood, of course, that the size and shape of the illuminatedarea may be varied at will by suitable adjustment of the relativeposition of the structural elements of the lighting set.

What I claim is:

A lighting set especially designed for dental use consisting of, anellipsoidal reflector, a small bulb light source in the reflectordisposed on the major optical axis thereof at one focal point of thereflector and positionable to localize theother focal point of thereflector at a patients mouth, a glass covering the light opening of thereflector and spaced parallel vertically extending wide flutes formed insaid glass with their convexities on the light source side of saidglass, said flutes being formed by narrow spaces between verticallyextending ridges arranged adjacent each other on the glass and thesurface of each ridge being a partial cylindrical surface and formingacute angles with the cylindrical surfaces of the adjacent ridges sothat rays of light from the light source directed toward the glass fromthe reflector are refracted by the..vertically extending ridges of theglass to form a rectangular area of light of intense illumination at apatients mouth.

References Cited in the file of this patent UNITED STATES PATENTS 4Alexander et a1. Dec. 31, 1935- Collins et a1. Sept. 24, 1940 KorengoldFeb. 11, 1941 Greppin Apr. 21, 1942 Ries et a1. Jan. 10, 1950 VersenJan. 26, 1954 Baker Apr. 13, 1954 Koch Jan. 15, 1957 FOREIGN PATENTSFrance Nov. 9, 1928 Canada June 14, 1949

